This invention relates to a structure for incorporating a fuel cell.
As shown in FIG. 1, a unit cell 8 constituting a fuel cell consists of a pair of gas diffusion electrodes 2, an electrolyte matrix 1 held between the electrodes 2, a carbon plate 5 having a parallel fuel (hydrogen) passages 4 at regular intervals on the upper surface off the upper electrode 2, and a carbon plate 7 having parallel air (oxygen) passages 6 at regular intervals on the lower surface of the lower electrode 2, the respective passages 4, 6 being crossed at right angles. When the fuel cell is made up by such unit cells 8, many layers of the unit cells 8 are alternately stacked with partition plates 9 and fixed on a base plate 11 which is fixed on two bars 12 diagonally crossed as shown in FIG. 2. Compression pads 14 equipped to upper bars 13 and diagonally crossed are put on the pressing plate 10 so that the cell layers 8 and the partition plates 9 are fastened by bolts 15 and nuts 16 at the ends of the upper and lower die bars 13, 12.
In the above structure incorporating the fuel cell fastened by the bolts 15 and the nuts 16 at the ends of the upper and lower die bars 13, 12, it is quite difficult to uniformly compress the entire surface by the four-point fastening by means of the compression pads. When the bolts 15 are expanded due to temperature rise, the cells 8 become loose and the air-tightness of the fuel (hydrogen) passages 4 and the air (oxygen) passages 6 is damaged, and an unevenness of the contact resistance is generated, resulting in a lowering of the output.